Usually, yes. Pick the garment you'd like first, then add Personalise It: Add Design to your cart and choose the design. It's $20, like the rest of Personalise It.
If the garment already carries a print, the second design goes on the opposite side, because we don't have plain versions of those. A graphic from a tee that has sold out can usually still be printed onto a current garment, so it's worth asking even if you can't find it on the site.
The limit is fabric. Where the print is part of the fabric itself, rather than a design printed on top, we can only make it into another style while we still have some of that fabric left. Email aroo@houndtees.com.au with the print and the style you're after and we'll check.

New arrivals
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New arrivals
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New arrivals
Sale